WO2019228354A1

WO2019228354A1 - Information feedback method, terminal, base station, storage medium and electronic device

Info

Publication number: WO2019228354A1
Application number: PCT/CN2019/088834
Authority: WO
Inventors: 吴昊; 鲁照华; 陈艺戬; 蒋创新; 张楠
Original assignee: 中兴通讯股份有限公司
Priority date: 2018-06-01
Filing date: 2019-05-28
Publication date: 2019-12-05
Also published as: CN110557176B; US11588530B2; EP3806343A1; US20210167833A1; EP3806343A4; CN110557176A

Abstract

Provided are an information feedback method, a terminal, a base station, a storage medium and an electronic device. The method comprises: decomposing a channel state information (CSI) matrix H to obtain matrices U _d and V _d, wherein U _d is a d-column matrix, and various column vectors are orthogonal pairwise; and V _d is a d-column matrix, and various column vectors are orthogonal pairwise; and feeding back amplitude and phase information of elements in d left feature vectors U _d, and/or, feeding back amplitude and phase information of elements in d right feature vectors V _d.

Description

Information feedback method, terminal, base station, storage medium, and electronic device

This application claims priority from a Chinese patent application filed with the Chinese Patent Office on June 01, 2018 with application number 201810556561.8, the entire contents of which are incorporated herein by reference.

Technical field

The present application relates to the field of communications, and in particular, to an information feedback method, terminal, base station, storage medium, and electronic device.

Background technique

In a related art Multiple Input Multiple Output (MIMO) wireless communication system, by precoding or beamforming multiple transmitting antennas, the purpose of improving transmission efficiency and reliability can be achieved. In order to achieve high-performance precoding or beamforming, the precoding matrix or beamforming vector needs a better matching channel, which requires that the transmitting end can better obtain channel state information (Channel State Information, CSI). Therefore, CSI feedback is a key technology to achieve high-performance precoding or beamforming in a MIMO system. However, when performing CSI feedback, the quantized feedback to the channel matrix will bring a relatively large feedback overhead, especially when supporting CSI feedback of multiple subbands, the feedback overhead is an important issue that limits performance improvement.

CSI quantized feedback technology is an important part of MIMO technology. In traditional wireless communication systems, Discrete Fourier Transform (DFT) vectors or DFT vector variations, such as the Kroneck product of multiple DFT vectors, or cascaded forms of DFT vectors, are commonly used. Or in the form of phase adjustment of the cascaded DFT vector, the terminal reports the precoding instruction information in the above form to the base station through quantized feedback. This type of precoding codebook can be classified as the first type of codebook. This type of codebook has less overhead, but its CSI quantization accuracy is lower and its performance is more limited. Another codebook uses linear weighting of the DFT vector or the Kronecker product of the DFT vector, and feeds the DFT vector-related information, the amplitude and phase information of the weighting coefficients as precoding instruction information to the base station. It can be classified as the second type of codebook. The CSI quantization accuracy of this codebook is high, but the CSI overhead is large, especially when linearly weighted combination of high rank or more DFT vectors will bring a large CSI feedback overhead. .

For the above problems in related technologies, no effective solution has been found.

Summary of the Invention

Embodiments of the present invention provide an information feedback method, a terminal, a base station, a storage medium, and an electronic device.

According to an embodiment of the present application, an information feedback method is provided, including: decomposing the CSI matrix H to obtain matrices U _d and V _d , where U _d is a matrix of d columns, and each column vector is mutually positive Intersect, V _d is a matrix of column d, and the vectors of each column are mutually orthogonal; feedback the amplitude and phase information of the elements in d left eigenvectors U _d , and / or, feedback the elements in d right eigenvectors V _d Amplitude and phase information.

According to an embodiment of the present application, an information feedback method is provided, including: receiving first amplitude and phase information of elements in d left feature vectors U _d fed back by a terminal UE, and / or, d right features fed back The second amplitude and phase information of the elements in the vector V _d , where U _d is a matrix of column d, each column vector is orthogonal to each other, V _d is a matrix of column d, and each column vector is orthogonal to each other Determining the first amplitude and phase information and / or the second amplitude and phase information as the channel state information CSI of the UE.

According to another embodiment of the present application, an information feedback terminal is provided, including: a decomposition module, configured to decompose a matrix H to obtain matrices U _d and V _d , where U _d is a matrix of d columns, and a vector of each column is Each pair is orthogonal to each other, V _d is a d column matrix, and each column vector is orthogonal to each other; a feedback module is used to feedback the amplitude and phase information of the elements in the d left eigenvectors U _d , and / or, The amplitude and phase information of the elements in the d right eigenvectors V _d is fed back.

According to another embodiment of the present application, an information feedback base station is provided, including: a receiving module, configured to receive first amplitude and phase information of elements in d left feature vectors U _d fed back by a terminal UE, and / or, The second amplitude and phase information of the elements in the feedback d right eigenvectors V _d , where U _d is a d column matrix, each column vector is orthogonal to each other, V _d is a d column matrix, and each of the column vectors The two are mutually orthogonal to each other; a determining module, configured to determine the first amplitude and phase information and / or the second amplitude and phase information as the channel state information CSI of the UE.

According to still another embodiment of the present application, a storage medium is further provided. The storage medium stores a computer program, and the computer program is configured to execute the steps in any one of the foregoing method embodiments when running.

According to another embodiment of the present application, an electronic device is further provided, which includes a memory and a processor. The memory stores a computer program, and the processor is configured to run the computer program to execute any one of the foregoing. Steps in a method embodiment.

Through this application, by using the information of the matrix vector to feed back the CSI, the technical problem of excessive feedback CSI overhead in the related art can be solved, and the resource utilization rate is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments of the present application and the descriptions thereof are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

FIG. 1 is a network architecture diagram according to an embodiment of the present invention;

2 is a flowchart of an information feedback method according to an embodiment of the present invention;

FIG. 3 is a flowchart of another information feedback method according to an embodiment of the present invention; FIG.

4 is a structural block diagram of an information feedback terminal according to an embodiment of the present invention;

5 is a structural block diagram of an information feedback base station according to an embodiment of the present invention;

6 is a schematic diagram of precoding information on each subband according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a three-dimensional matrix space according to an embodiment of the present invention.

Detailed ways

Hereinafter, the present application will be described in detail with reference to the drawings and embodiments. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

It should be noted that the terms “first” and “second” in the specification and claims of the present application and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

Example 1

The embodiment of the present application may run on the network architecture shown in FIG. 1, as shown in FIG. 1, which is a network architecture diagram of an embodiment of the present invention. The network architecture includes a terminal and a base station, and the terminal interacts with the base station. .

In this embodiment, an information feedback method running on the network architecture is provided. FIG. 2 is a flowchart of an information feedback method according to an embodiment of the present invention. As shown in FIG. 2, the process includes the following steps:

In step S202, the CSI matrix H is decomposed to obtain the matrices U _d and V _d , where U _d is a matrix of d columns, each column vector is orthogonal to each other, V _d is a matrix of d column, and each of the column vectors is two Two mutually orthogonal

In step S204, the amplitude and phase information of the elements in the d left feature vectors U _d are fed back, and / or the amplitude and phase information of the elements in the d right feature vectors V _d are fed back.

Through the above steps, by using the information of the matrix vector to feedback the CSI, the technical problem of excessive feedback CSI overhead in the related art can be solved, and the resource utilization rate is improved.

Optionally, the execution subject of the above steps may be a terminal, such as a mobile phone, but is not limited thereto.

Optionally, decomposing the matrix H to obtain the matrices U _d and V _d includes: decomposing the matrix H to obtain singular value decomposition (Singularly Valuable Decomposition, SVD) to obtain the matrices U _d and V _d .

In this embodiment, SVD decomposition, that is, the matrix is written as the product of the three matrices UDV ^H ; eigenvectors, which can also be called singular vectors, orthogonal basis vectors, etc .; eigenvalues, that is, pairs of intermediate matrices after SVD decomposition or eigenvalue decomposition Corner line element. After the ranks and columns are swapped in the embodiment, or the left and right are swapped, the solution in this embodiment is still applicable.

Optionally, the matrix H is a matrix formed by combining precoding matrices on subbands of the r-th layer, where 1≤r≤R, r is an integer, and R is the total number of channels.

Optionally, after the matrix H is decomposed to obtain the matrices U _d and V _d , the method further includes: feeding back a subband channel quality indicator (Channel Quality Indicator, CQI).

Optionally, the precoding matrix assumed for the CQI calculation of the m-th subband is obtained according to the following manner: For the m-th subband, after multiplying U _d and V _d ^{H of} each layer in each layer, corresponding to the m-th subband A matrix formed by the combination of column vectors, V _d ^H is the conjugate transpose of V _d .

Optionally, the value of d is determined according to at least one of the following methods: base station configuration signaling; the number of feature values greater than the first threshold determined as d according to a first threshold determined by the terminal or configured by the base station; d according to the terminal The second threshold value determined or configured by the base station determines the number of feature values whose ratio of the average value of all feature values to the minimum value of all feature values is greater than the second threshold value as d.

Optionally, decomposing the matrix H to obtain the matrices U _d and V _d includes: the matrix H includes weighting coefficients for weighting and merging L codebook base vectors, where L is an integer greater than 1.

Optionally, the matrix H is a matrix of M rows and 2L columns, and M is the number of subbands included in the CSI feedback bandwidth.

Optionally, the elements of the m-th row and the n-th column of the matrix H are at least one of the following:

When n <= L, the weighting coefficient of the nth codebook base vector on the first half antenna port on the mth subband;

When n> L, the weight coefficients of the n-Lth codebook vector with respect to the second half antenna port on the mth subband.

Optionally, the matrix H is a matrix formed by joint CSI of the R layer.

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, wherein the number of rows of the matrix of the e-th SVD decomposition is equal to at least one of the following: the number of antenna ports, the number of codebook base vectors, or the number of codebook base vectors 2 times, the number of subbands, the number of channel layers, and e is an integer greater than or equal to 1, and less than or equal to E.

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, wherein the number of columns of the matrix of the e-th SVD decomposition is equal to at least one of the following: the number of antenna ports, the number of codebook base vectors, or the number of codebook base vectors 2 times, the number of subbands, the number of channel layers, the product of at least two of the following parameters: the number of antenna ports, the number of codebook base vectors or the number of codebook base vectors, the number of subbands, the channel layer Number; e is an integer greater than or equal to 1 and less than or equal to E.

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, where the number of the corresponding element in the matrix of the e-th SVD decomposition is obtained by linear transformation of at least one of the port number, the subband number, and the layer number.

Optionally, the matrix H satisfies at least one of the following:

The number of rows is equal to the number of subbands, the number of columns is equal to the product of the number of ports and the number of layers, the mth row, n + (r-1) N column, or the mth row, r + (n-1) R column element The n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

The number of rows is equal to the number of antenna ports, and the number of columns is equal to the product of the number of subbands and the number of layers. The nth row, m + (r-1) M column, or the nth row, r + (m-1) R column The elements are the n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

The number of rows is equal to the number of layers, and the number of columns is equal to the product of the number of subbands and the number of antenna ports. The rth row, m + (n-1) M column, or the rth row, n + (m-1) N column The elements are the n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

Among them, N is the number of antenna ports of the channel state information reference signal CSI-RS, and M is the number of subbands included in the CSI feedback bandwidth.

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, and feedbacks the amplitude and phase information of the elements in the d left feature vectors U _d corresponding to each decomposition, and / or, feedbacks the d right features corresponding to each decomposition. Amplitude and phase information of the elements in the vector V _d .

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, and the pre-coding matrix assumed by the feedback subband CQI calculation is obtained according to a transposed matrix product of U _d ^e and V _d ^e , where V _d ^e is a division e The d left eigenvectors obtained by the E-1 times of SVD decomposition constitute the first d columns of the Kronecker product of the matrix, and U _d ^e is a matrix composed of the d left eigenvectors obtained by the e-th SVD decomposition.

Optionally, the elements in the precoding matrix assumed by the subband CQI are obtained according to corresponding elements after linear transformation of row or column numbering of the matrix product.

In this embodiment, an information feedback method running on the network architecture is provided. FIG. 3 is a flowchart of another information feedback method according to an embodiment of the present invention. As shown in FIG. 3, the process includes the following steps:

Step S302: Receive first amplitude and phase information of elements in d left eigenvectors U _d fed back by the terminal UE, and / or second amplitude and phase information of elements in d right eigenvectors V _d fed back, where: U _d is a matrix of column d, and each column vector is orthogonal to each other, and V _d is a matrix of column d, and each column vector is orthogonal to each other;

Step S304: Determine the first amplitude and phase information and / or the second amplitude and phase information as the channel state information CSI of the UE.

Optionally, the matrices U _d and V _d are matrices obtained by performing singular value decomposition SVD on the matrix H.

Optionally, after the matrix H is decomposed to obtain the matrices U _d and V _d , the method further includes: receiving a subband channel quality indicator CQI fed back by the terminal.

Optionally, the precoding matrix assumed for the CQI calculation of the m-th subband is obtained according to the following manner: For the m-th subband, after multiplying U _d and V _d ^{H of} each layer in each layer, corresponding to the m-th subband A matrix of column vector unions.

Optionally, the value of d is determined according to at least one of the following ways:

Base station configuration signaling;

Determining the number of feature values larger than the first threshold as d according to the first threshold determined by the terminal or configured by the base station;

According to the second threshold determined by the terminal or configured by the base station, the number of feature values whose ratio of the average value of all feature values to the minimum value of all feature values is greater than the second threshold value is determined as d.

Optionally, the matrix H is a matrix formed by joint CSI of the R layer.

Optionally, the decomposition matrix H includes S≥1 times of SVD decomposition, wherein the number of rows of the matrix of the e-th SVD decomposition is equal to at least one of the following:

The number of antenna ports, the number of codebook base vectors or the number of codebook base vectors, the number of subbands, the number of channel layers, 1≤e≤E, e is an integer.

Optionally, the decomposition matrix H includes S≥1 SVD decomposition, wherein the number of columns of the matrix of the e-th SVD decomposition is equal to at least one of the following:

The number of antenna ports, the number of codebook base vectors or the number of codebook base vectors, the number of subbands, the number of channel layers, the product of at least two of the following parameters: the number of antenna ports, the number of codebook base vectors, or 2 times the number of codebook base vectors, the number of subbands, and the number of channel layers;

1≤e≤E, e is an integer.

Optionally, the matrix H satisfies at least one of the following:

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, receives amplitude and phase information of elements in d left feature vectors U _d corresponding to each decomposition, and / or receives d right features corresponding to each decomposition Amplitude and phase information of the elements in the vector V _d .

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, and the precoding matrix assumed by the received subband CQI calculation is obtained according to a transposed matrix product of U _d ^e and V _d ^e , where V _d ^e is a division e The d left eigenvectors obtained by the E-1 times SVD decomposition constitute the first d columns of the Kronecker product of the matrix, and U _d ^e is a matrix composed of the d left eigenvectors obtained by the eth SVD decomposition.

Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be implemented by means of software plus a necessary universal hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is Better implementation. Based on such an understanding, the technical solution of the present invention, in essence, or a part that contributes to the existing technology, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, The optical disc) includes several instructions for causing a terminal device (which may be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of the embodiments of the present application.

Example 2

An information feedback device is also provided in this embodiment, which is used to implement the foregoing embodiments and preferred implementation manners, and the descriptions will not be repeated. As used below, the term "module" may implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and conceived.

FIG. 4 is a structural block diagram of an information feedback terminal according to an embodiment of the present invention. As shown in FIG. 4, the apparatus includes:

The decomposition module 40 is used to decompose the matrix H to obtain the matrices U _d and V _d , where U _d is a matrix of d columns, each column vector is orthogonal to each other, V _d is a matrix of d column, and each of the column vectors is The two are orthogonal to each other;

The feedback module 42 is configured to feed back the amplitude and phase information of the elements in the d left eigenvectors U _d , and / or, feed back the amplitude and phase information of the elements in the d right eigenvectors V _d .

Optionally, the matrix H is a matrix formed by joint CSI of the R layer.

Optionally, the matrix H satisfies at least one of the following:

FIG. 5 is a structural block diagram of an information feedback base station according to an embodiment of the present invention. As shown in FIG. 5, the apparatus includes:

The receiving module 50 is configured to receive first amplitude and phase information of elements in d left eigenvectors U _d fed back by the terminal UE, and / or second amplitude and phase information of elements in d right eigenvectors V _d fed back. , Where U _d is a matrix of d column, each column vector is orthogonal to each other, V _d is a matrix of d column, and each column vector is orthogonal to each other;

The determining module 52 is configured to determine the first amplitude and phase information and / or the second amplitude and phase information as the channel state information CSI of the UE.

Base station configuration signaling;

Optionally, the matrix H is a matrix formed by joint CSI of the R layer.

1≤e≤E, e is an integer.

Optionally, the matrix H satisfies at least one of the following:

The number of rows is equal to the number of antenna ports, and the number of columns is equal to the product of the number of subbands and the number of layers. The nth row, m + (r-1) M column, or the nth row The elements are the n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

Optionally, the decomposition matrix H includes E≥1 SVD decomposition, and the precoding matrix assumed by the received subband CQI calculation is obtained according to a transposed matrix product of U _d ^e and V _d ^e , where V _d ^e is a division e The d left eigenvectors obtained by the E-1 times of SVD decomposition constitute the first d columns of the Kronecker product of the matrix, and U _d ^e is a matrix composed of the d left eigenvectors obtained by the e-th SVD decomposition.

It should be noted that each of the above modules can be implemented by software or hardware. For the latter, it can be implemented by the following methods, but is not limited to this: the above modules are all located in the same processor; or the above modules are arbitrarily combined The forms are located in different processors.

Example 3

The terminal performs SVD decomposition according to the R layer CSI on the M subbands and N antenna ports, and feeds back amplitude and phase information of elements in d left feature vectors U _d and / or d right feature vectors V _d .

The matrix for SVD decomposition is a matrix combining the precoding matrices recommended or preferred by the terminal on each subband for the r-th layer.

The terminal feeds back the subband CQI. The precoding matrix for the mth subband CQI calculation hypothesis. According to the subband, after multiplying U _d and V _d ^{H of} each layer in each layer, the column vectors corresponding to the subband are jointly formed. The matrix is obtained.

The value of d is determined according to at least one of the following methods:

Base station configuration signaling;

d left special vectors, and / or d right eigenvectors, associated with d eigenvalues;

According to the determined or configured threshold of the base station, the number of characteristic values larger than the threshold is d, and the terminal reports the value of d to the base station;

According to the determined or configured threshold value of the base station, and the ratio of the average value of all feature values (or the minimum value of all feature values) to the feature value greater than the threshold is d, the terminal reports the value of d to the base station.

The CSI of SVD decomposition is a weighting coefficient for weighting and merging L codebook base vectors, and the matrix of SVD decomposition is a matrix of M rows and 2L columns.

The elements in row m and column n are at least one of the following:

When n <= L, the weighting coefficient of the nth codebook base vector on the first half of the antenna ports on the mth subband;

When n> L, the weight coefficient of the n-Lth codebook vector with respect to the second half antenna port on the mth subband.

The matrix for SVD decomposition is a matrix formed by the CSI of the R layer.

Each time the CSI feedback is performed, K> = 1 SVD decomposition, and the number of rows of the k-th SVD decomposition matrix is equal to at least one of the following:

Number of antenna ports;

The number of codebook base vectors or twice the number of codebook base vectors;

Number of subbands;

Number of layers (channel rank);

Perform K> = 1 SVD decomposition for each CSI feedback, and the number of columns of the k-th SVD decomposition matrix is equal to the product of at least two of the following: the number of antenna ports; the number of codebook base vectors or the number of codebook base vectors 2 Times; the number of subbands; the number of layers (channel rank).

For each CSI feedback, K> = 1 SVD decomposition is performed, and the number of the corresponding element in the k-th SVD decomposition matrix is obtained by linear transformation of at least one of the port number, the subband number, and the layer number.

Further, the matrix H satisfies at least one of the following:

The number of rows is equal to the number of subbands, the number of columns is equal to the product of the number of ports and the number of layers, the mth row, n + (r-1) N column, or the mth row, r + (n-1) R column element A precoding coefficient recommended or preferred by the terminal on the n-th port, the m-th subband, and the terminal on the r-th layer;

The number of rows is equal to the number of antenna ports, and the number of columns is equal to the product of the number of subbands and the number of layers. The nth row, m + (r-1) M column, or the nth row, r + (m-1) R column The elements are the precoding coefficients recommended or preferred by the terminal on the nth port, the mth subband, and the rth layer;

The number of rows is equal to the number of layers, and the number of columns is equal to the product of the number of subbands and the number of antenna ports. The rth row, m + (n-1) M column, or the rth row, n + (m-1) N column The elements are the n-th port, the m-th subband, and the precoding coefficient recommended or preferred by the terminal on the r-th layer.

Each time the CSI feedback is performed, K> = 1 SVD decomposition, and the terminal feedbacks a matrix U _d ^k composed of d left eigenvectors obtained by each SVD decomposition, or a matrix V _d ^k composed of d right eigenvectors.

The terminal feeds back the sub-band CQI, and the pre-coding of the sub-band CQI calculation hypothesis is obtained according to the transposed matrix product of U _d ^k and V _d ^k .

V _d ^k is the first d columns of the Kronecker product of the d left eigenvectors obtained from the K-1 times of SVD decomposition except k.

The elements in the precoding matrix assumed by the subband CQI are obtained according to the corresponding elements after linear transformation of row or column numbers of the matrix product.

In this embodiment, the row and column swap, or the left and right swap, the features still hold; SVD decomposition, that is, the matrix is written as the product of the three matrices UDV ^H ; the feature vector can also be called singular vector, orthogonal basis vector, etc. ; Eigenvalues, that is, diagonal elements of the intermediate matrix after eigenvalue decomposition.

This embodiment also includes the following implementations:

Embodiment 1: Separate processing of each layer

In this application, a method for phase and / or amplitude compression of channel coefficients in frequency domain and space domain is proposed for CSI feedback.

The terminal obtains the wideband RI information of the CSI feedback bandwidth and each subband of the CSI feedback bandwidth according to the measurement reference signal, such as a precoding matrix. 6 is a schematic diagram of precoding information on each subband according to an embodiment of the present invention. As shown in FIG. 6, in a system in which the number of antenna ports is N and the CSI feedback bandwidth includes M subbands, the broadband RI indicates that there are R layers in total, The CSI of the layer is shown in Figure 6.

Specifically, the CSI of each subband in each layer corresponding to each antenna port is a matrix H of N × M, and the elements in the nth row and mth column of H are h _{n, m} , which represents the nth antenna port, and the mth CSI coefficients on the subbands, that is,

In the above example of CSI, the m-th column vector in H

Represents a precoding vector recommended or preferred by the terminal in the mth subband on a certain layer.

The terminal pair obtains the CSI matrices U _d and V _d according to the above matrix H, where U _d is a matrix of N rows and d columns, and each column vector is orthogonal to each other. V _d is a matrix of M rows and d columns, and each column vector The two are orthogonal to each other. Further, the modulus of each column vector of U _d and V _d is 1. For example, the terminal performs SVD decomposition on the above matrix H to obtain the following matrices U and V,

H = UDV ^H

From the above U and V, d column vectors are selected. For example, d column vectors in U and V corresponding to the largest d diagonal elements in D form the matrices U _d and V _d . The value of d is notified to the terminal by the base station through signaling, or the terminal determines and reports the value to the base station by comparing the amplitude of each diagonal element in D. The method may be determined: The determined threshold value D is greater than the threshold value corresponding to the diagonal elements U, V in the selected column vector U _d and V _d; or, according to the determined threshold value, the diagonal elements of D In the case where the ratio of the average values of all diagonal elements in and D exceeds this threshold, the corresponding U and V column vectors are selected into U _d and V _d .

The terminal reports amplitude and phase information of each element in U _d and V _d corresponding to the RI and each layer.

In the above manner, a certain feedback overhead can be reduced and CSI feedback with higher accuracy can be realized.

The following three implementations of this embodiment solve the following problems involved in this method: if a multi-layer channel is calculated, how to consider the compression feedback of the multi-layer channel, and what assumptions are used to calculate the subband CQI, and the traditional second The method of combining class codebooks is to feedback the subband amplitude and phase coefficients in the traditional second class through the above-mentioned methods.

Embodiment 2: Multi-layer joint processing

Consider N ₁ = N antenna ports, n ₁ ∈ {1, ..., N ₁ }, N ₂ = M subbands, n ₂ ∈ {1,…, N ₂ }, N ₃ = R layers, n ₃ ∈ For the channel information of {1,…, N ₃ }, a matrix of N ₁ × N ₂ × N ₃ in a three-dimensional matrix space can be used.

It is shown in FIG. 7, which is a schematic diagram of a three-dimensional matrix space according to an embodiment of the present invention.

The element at the (n ₁ , n ₂ , n ₃ ) position is

N ₂ represents subbands, the n ₁ first antenna port CSI coefficient of n-th layer _3. Further, for example, on the n _2nd subband, the precoding matrix recommended or preferred by the terminal is a matrix H _m of N ₁ × N ₃ , and the elements of the n _1th row and _3rd column are

Extracting feature vectors in each dimension of the three-dimensional matrix is achieved by high-order SVD decomposition (HOSVD)

Among them, U ₁ , U ₂ , and U ₃ are respectively a matrix composed of feature vectors in three dimensions. The column vector in U ₁ is an N × 1 vector, and the column vector in U ₂ is an M × 1 vector. U ₃ The column vectors in are R × 1 vectors. Further, the column vectors of U ₁ , U ₂ and U ₃ are all vectors of modulo 1.

In the above formula (1) of HOSVD, the operation symbol × _k represents a _k- th multiplication of a high-order matrix. An expression representing the above three-dimensional space in a two-dimensional matrix space.

SVD decomposition, then U ₁ , U ₂ , U _{3 in} (1) can be obtained by the following expression

Where K = 3 and k = 1,2,3. among them,

Representing higher-order matrices

Expand the matrix in the k-th dimension. The dimensions of the matrix are N _k × N ₁ … N _k-1 N _{k + 1} … N _K. Specifically,

Where (n ₁ , n ₂ , ..., n _K ) to (m, n) are mapped as

Three-dimensional matrix specific to this method

among them,

m = n ₁

n = n ₂ + (n ₃ -1) N ₂

And

among them

m = n ₂

n = n ₁ + (n ₃ -1) N ₁

And

among them

m = n ₃

n = n ₁ + (n ₂ -1) N ₁

Therefore, according to formula (2),

SVD decomposition is performed to obtain three left feature matrices U ₁ , U ₂ , and U ₃ . Take d feature vectors for U ₁ , U ₂ , and U ₃ respectively

E.g,

The column vectors in are the column vectors of U ₁ , U ₂ , and U ₃ corresponding to the largest d diagonal elements in D ₁ , D ₂ , and D ₃ respectively. Terminal feedback

Amplitude and phase information of the element. After the base station obtains the feedback feature vector, it constructs a three-dimensional space matrix according to the following formula

among them,

Representation matrix

A matrix consisting of the first d columns in order.

Embodiment 3: Subband CQI

In the above feedback method, a feedback subband CQI is further added, and the base station can obtain the precoder of the subband and the MCS of the subband after processing. In this case, the precoding matrix assumed in the subband CQI calculation is a matrix that is distributed on each subband after the reported matrix is multiplied and other processing.

Specifically, if the feedback is processed separately for each layer, based on the SVD decomposition of the two-dimensional matrix, it is assumed that the feedback matrix of the r-th layer is

with

Where r = 1, ..., R, then the precoding matrix assumed for the CQI calculation of the n _2nd subband is

That is, the precoding matrix assumed for the CQI calculation of the n _2nd subband is F, and F (a, b) = G _b (a, n ₂ ),

If the feedback is jointly processed by all layers, it is reported based on HOSVD

The precoding assumption for the terminal to calculate the CQI is based on k = 1,2 or 3.

Get, where,

Representation matrix

A matrix consisting of the first d columns in order. according to

And the mapping method given in scheme 1, can be a two-bit space

Convert to N ₁ x N ₂ x N ₃ three-dimensional space matrix

Take k = 2 as an example,

Express

A matrix consisting of the first d columns of

x = 1, ..., N ₁ N ₃ , y = 1, ..., d. ; The precoding assumed for the CQI calculation of the nth _2nd subband is

That is, the assumed precoding matrix on the _2nd subband is F,

Where s = a + (b-1) N ₁ .

Embodiment 4: feedback in combination with the traditional second type codebook

When the second type of codebook is configured for feedback, one way is to weight-merge the L codebook base vectors to obtain N ₁ = 2L codebook base vectors, N ₂ = M subbands, and N ₃ = R The layer, according to the method in scheme 0 or scheme 1, obtains and feeds back the CSI through separate processing of the layers or joint processing of the layers. Specifically, there are the following two sub-methods.

Sub-Method A:

For N antenna ports, the weighting coefficient of each subband corresponding to each codebook base vector in each layer is a matrix L of 2L × M, and the elements of the nth row and mth column of H are h _{n, m} , when n <= At L, h _{n, m} indicates that the nth codebook base vector corresponds to the first half of the antenna ports (ie, port 1 to port N / 2), and the weighting coefficient on the subband m. When n> L, h _{n, m} Represents the weighting coefficient on the subband m of the nL codebook base vector corresponding to the second half antenna port (ie, port N / 2 + 1-port N). therefore,

The terminal pair obtains the matrices U _d and V _d according to the above matrix H, where U _d is a matrix of 2L rows and d columns, and the column vectors are orthogonal to each other. V _d is a matrix of M rows and d columns. Between each other are orthogonal to each other. Further, the modulus of each column vector of U _d and V _d is 1. For example, the terminal performs SVD decomposition on the above matrix H to obtain the following matrices U and V,

H = UDV ^H

From the above U and V, d column vectors are selected. For example, d column vectors in U and V corresponding to the largest d diagonal elements in D form the matrices U _d and V _d . The value of d is notified to the terminal by the base station through signaling, or the terminal determines and reports the value to the base station by comparing the amplitude of each diagonal element in D. The method may be determined: The determined threshold value D is greater than the threshold value corresponding to the diagonal elements U, V in the selected column vector U _d and V _d; or, according to the determined threshold value, the diagonal elements of D If the ratio of the average values of all diagonal elements in D and D exceeds this threshold, the corresponding U and V column vectors are selected into U _d and V _d .

The terminal reports RI = R, indicating the PMI of the codebook base vector and the amplitude and phase information of each element in U _d and V _d corresponding to each layer. The feedback matrix of the r-th layer is

with

The terminal reports the subband CQI. On the mth subband, the precoding assumption of the subband CQI calculation is

Where W ₁ (p, l) = v _l (p),

v ₁ , ..., v _L are L codebook basis vectors, c _{n, r} (m) = G _r ( _n , m),

Sub-Method B:

For N antenna ports, consider L codebook basis vectors, N ₁ = 2L and n ₁ ∈ {1, ..., N ₁ }, N ₂ = M subbands n ₂ ∈ {1, ..., N ₂ }, N ₃ = channel information of R layers n ₃ ∈ {1, ..., N ₃ }, a matrix of N ₁ × N ₂ × N ₃ in a three-dimensional matrix space can be used

(As shown in Figure 7), where

The element at the (n ₁ , n ₂ , n ₃ ) position is

When n ₁ ≤L,

N ₂ represents the subbands in the n-th layer _3, the first n _1-yl codebook vector corresponding to the first half of antenna ports (i.e., port 1 - port N / 2) of the weighting factor, n _1> L,

Represents that on the n _2nd subband, the n ₁ -L codebook base vectors are on the n _3rd layer and correspond to the weighting coefficients of the latter half of the antenna ports (ie, port N / 2 + 1-port N).

Among them, U ₁ , U ₂ , and U ₃ are respectively a matrix composed of feature vectors in three dimensions. The column vector in U ₁ is an N × 1 vector, the column vector in ₂ is an M × 1 vector, and U ₃ The column vector of R is a vector of R × 1. Further, the column vectors of U ₁ , U ₂ and U ₃ are all vectors of modulo 1.

Where K = 3 and k = 1,2,3. among them,

Representing higher-order matrices

Expand the matrix in the k-th dimension. The dimensions of the matrix are N _k × N ₁ … N _k-1 N _{k + 1} … N _K. Specific to the three-dimensional matrix in this method:

among them,

m = n ₁

n = n ₂ + (n ₃ -1) N ₂

And

among them

m = n ₂

n = n ₁ + (n ₃ -1) N ₁

And

among them

m = n ₃

n = n ₁ + (n ₂ -1) N ₁

Therefore, according to formula (2),

E.g,

The column vectors in are the column vectors of U ₁ , U ₂ , and U ₃ corresponding to the largest d diagonal elements in D ₁ , D ₂ , and D ₃ respectively. The terminal reports RI = R, indicating the PMI and

Amplitude and phase information of the element. For k = 1,2 or 3

among them,

Representation matrix

A matrix consisting of the first d columns in order.

When calculating the CQI for the n _2nd subband, the assumed precoding is

Where W ₁ (p, l) = v _l (p),

s = a + (b-1) N ₁ ,

Express

Matrix consisting of the first d columns in sequence, ie

x = 1, ..., N ₁ N ₃ , y = 1, ..., d.

Example 4

An embodiment of the present application further provides a storage medium. The storage medium stores a computer program, and the computer program is configured to execute the steps in any one of the foregoing method embodiments when running.

Optionally, in this embodiment, the foregoing storage medium may be configured to store a computer program for performing the following steps:

S1, the matrix H is decomposed to obtain the matrices U _d and V _d , where U _d is a matrix of column d, each column vector is orthogonal to each other, V _d is a matrix of column d, and each column vector is mutually Orthogonal

S2, feedback the amplitude and phase information of the elements in the d left eigenvectors U _d , and / or, feedback the amplitude and phase information of the elements in the d right eigenvectors V _d .

Optionally, in this embodiment, the foregoing storage medium may include, but is not limited to, a U disk, a read-only memory (ROM), a random access memory (Random Access Memory, RAM), A variety of media that can store computer programs, such as removable hard disks, magnetic disks, or optical disks.

An embodiment of the present application further provides an electronic device including a memory and a processor. The memory stores a computer program, and the processor is configured to run the computer program to perform the steps in any one of the foregoing method embodiments.

Optionally, the electronic device may further include a transmission device and an input-output device, wherein the transmission device is connected to the processor, and the input-output device is connected to the processor.

Optionally, in this embodiment, the foregoing processor may be configured to execute the following steps by a computer program:

Optionally, for specific examples in this embodiment, reference may be made to the examples described in the foregoing embodiments and optional implementation manners, and details are not described herein again in this embodiment.

Obviously, those skilled in the art should understand that the above-mentioned modules or steps of the present application may be implemented by a general-purpose computing device, and they may be concentrated on a single computing device or distributed on a network composed of multiple computing devices. Above, optionally, they may be implemented with program code executable by a computing device, so that they may be stored in a storage device and executed by the computing device, and in some cases, may be in a different order than here The steps shown or described are performed, or they are separately made into individual integrated circuit modules, or multiple modules or steps in them are made into a single integrated circuit module for implementation. As such, the invention is not limited to any particular combination of hardware and software.

The above are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, this application may have various modifications and changes. Any modification, equivalent replacement, or improvement made within the principle of the present invention shall be included in the protection scope of the present application.

Claims

An information feedback method includes:

The channel state information CSI matrix H is decomposed to obtain the matrices U d and V d . Among them, U d is a matrix of d columns, and the multi-column vectors are orthogonal to each other. V d is a matrix of d columns. Two mutually orthogonal

At least one of the following information is fed back: the amplitude and phase information of the elements in the d left eigenvectors U d , and the amplitude and phase information of the elements in the d right eigenvectors V d .
The method according to claim 1, wherein decomposing the CSI matrix H to obtain the matrices U d and V d comprises:

The CSI matrix H is subjected to singular value decomposition SVD to obtain matrices U d and V d .
The method according to claim 1, wherein the matrix H is a matrix formed by combining precoding matrices on multiple subbands for the r-th layer, wherein 1≤r≤R, r is an integer, and R Is the total number of layers in the channel.
The method according to claim 1, wherein after decomposing the CSI matrix H to obtain the matrices U d and V d , further comprising:

The feedback subband channel quality indicates CQI.
The method according to claim 4, wherein the precoding matrix assumed by the CQI calculation of the m-th subband is obtained according to the following manner: for the m-th subband, after U d and V d H of each of the multiple layers are multiplied A matrix corresponding to the column vectors of the mth subband, V d H is the conjugate transpose of V d .
The method according to claim 1, wherein the value of d is determined according to at least one of the following ways:

Base station configuration signaling;

Determining the number of feature values greater than the first threshold as d according to the first threshold determined by the terminal or configured by the base station;

According to the second threshold determined by the terminal or configured by the base station, the number of feature values whose ratio to the average value of all feature values is greater than the second threshold is determined as d or the ratio to the minimum value of all feature values is greater than The number of eigenvalues of the second threshold is determined as d.
The method according to claim 1, wherein:

The matrix H includes weighting coefficients for weighting and merging L codebook base vectors, where L is an integer greater than 1.
The method according to claim 7, wherein the matrix H is a matrix of M rows and 2L columns, and M is a number of subbands included in a CSI feedback bandwidth.
The method according to claim 8, wherein the elements of the m-th row and the n-th column of the matrix H are at least one of the following:

In the case of n <= L, on the mth subband, the weighting coefficient of the nth codebook base vector with respect to the first half of the antenna ports;

In the case of n> L, on the m-th subband, the weight coefficient of the n-Lth codebook vector with respect to the latter half of the antenna port.
The method according to claim 2, wherein the matrix H is a matrix formed by joint CSI of R layers.
The method according to claim 10, wherein the decomposition matrix H comprises E≥1 SVD decomposition, wherein the number of rows of the matrix of the e-th SVD decomposition is equal to at least one of the following:

The number of antenna ports, the number of codebook base vectors or the number of codebook base vectors, the number of subbands, the number of channel layers, 1≤e≤E, e is an integer.
The method according to claim 10, wherein the decomposition matrix H comprises E≥1 SVD decomposition, and the number of columns of the matrix of the e-th SVD decomposition is equal to at least one of the following:

The number of antenna ports, the number of codebook base vectors or the number of codebook base vectors, the number of subbands, the number of channel layers, the product of at least two of the following parameters: the number of antenna ports, the number of codebook base vectors, or 2 times the number of codebook base vectors, the number of subbands, and the number of channel layers;

1≤e≤E, e is an integer.
The method according to claim 10, wherein the decomposition matrix H comprises E≥1 SVD decomposition, and the number of corresponding elements in the matrix of the e-th SVD decomposition is at least one of port number, subband number, and layer number. Obtained by linear transformation.
The method according to claim 10, wherein the matrix H satisfies at least one of the following:

The number of rows is equal to the number of subbands, the number of columns is equal to the product of the number of ports and the number of layers, the mth row, n + (r-1) N column, or the mth row, r + (n-1) R column element The n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

The number of rows is equal to the number of antenna ports, and the number of columns is equal to the product of the number of subbands and the number of layers. The nth row, m + (r-1) M column, or the nth row, r + (m-1) R column The elements are the n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

The number of rows is equal to the number of layers, and the number of columns is equal to the product of the number of subbands and the number of antenna ports. The rth row, m + (n-1) M column, or the rth row, n + (m-1) N column The elements are the n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

Among them, N is the number of antenna ports of the channel state information reference signal CSI-RS, M is the number of subbands included in the CSI feedback bandwidth, and R is the number of layers.
The method according to claim 10, wherein the decomposition matrix H comprises E≥1 SVD decomposition, and feedbacks at least one of the following: amplitude and phase information of elements in the d left feature vectors U d corresponding to each decomposition, and each The amplitude and phase information of the elements in the d right eigenvectors V d corresponding to the secondary decomposition.
The method according to claim 10, wherein the decomposition matrix H comprises E≥1 SVD decomposition, and the precoding matrix assumed by the feedback subband CQI calculation is obtained according to a matrix product of transposed U d e and V d e , where , Where V d e is the first d column of the Kronecker product of the d left eigenvectors obtained by E-1 times of SVD decomposition other than e, and U d e is the d number of e-th SVD decompositions A matrix of left feature vectors.
The method according to claim 16, wherein the elements in the precoding matrix assumed by the subband CQI are obtained according to corresponding elements obtained by linearly transforming a product of the matrix U d and V d by row numbering or column numbering.
An information feedback method includes:

Receive at least one of the following information fed back by the terminal UE: first amplitude and phase information of elements in d left eigenvectors U d , and second amplitude and phase information of elements in d right eigenvectors V d , where U d is a matrix of column d, and the vectors of multiple columns are orthogonal to each other; V d is a matrix of column d, and the vectors of multiple columns are orthogonal to each other;

At least one of the first amplitude and phase information and the second amplitude and phase information is determined as the channel state information CSI of the UE.
The method according to claim 18, wherein the U d and V d are matrices obtained by performing singular value decomposition SVD decomposition of the CSI matrix H.
The method according to claim 19, wherein the matrix H is a matrix formed by combining precoding matrices on multiple subbands for the r-th layer, wherein 1≤r≤R, r is an integer, and R Is the total number of layers in the channel.
The method of claim 19, further comprising:

Receiving a subband channel quality indication CQI fed back by the UE.
The method according to claim 21, wherein the precoding matrix assumed for the CQI calculation of the m-th subband is obtained according to the following manner: for the m-th subband, after multiplying U d and V d H of each of a plurality of layers A matrix corresponding to the column vectors of the mth subband, V d H is the conjugate transpose of V d .
The method according to claim 18, wherein the value of d is determined according to at least one of the following ways:

Base station configuration signaling;

d is a number of feature values larger than a first threshold, where the first threshold is a threshold determined by the UE or configured by a base station;

d is the number of eigenvalues whose ratio to the average of all eigenvalues is greater than the second threshold or the number of eigenvalues whose ratio to the minimum of all eigenvalues is greater than the second threshold, where the second threshold is A threshold determined by the UE terminal or configured by a base station.
The method according to claim 19, wherein:

The matrix H includes weighting coefficients for weighting and merging L codebook base vectors, where L is an integer greater than 1.
The method according to claim 24, wherein the matrix H is a matrix of M rows and 2L columns, and M is a number of subbands included in a CSI feedback bandwidth.
The method according to claim 25, wherein the elements of the m-th row and the n-th column of the matrix H are at least one of the following:

In the case of n <= L, on the mth subband, the weighting coefficient of the nth codebook base vector with respect to the first half of the antenna ports;

In the case of n> L, on the m-th subband, the weight coefficient of the n-Lth codebook vector with respect to the latter half of the antenna port.
The method according to claim 19, wherein the matrix H is a matrix formed by joint CSI of R layers.
The method according to claim 27, wherein the decomposition matrix H comprises E≥1 SVD decomposition, wherein the number of rows of the matrix of the e-th SVD decomposition is equal to at least one of the following:

The number of antenna ports, the number of codebook base vectors or the number of codebook base vectors, the number of subbands, the number of channel layers, 1≤e≤E, e is an integer.
The method according to claim 26, wherein the decomposition matrix H comprises S≥1 SVD decomposition, and the number of columns of the matrix of the e-th SVD decomposition is equal to at least one of the following:

The number of antenna ports, the number of codebook base vectors or the number of codebook base vectors, the number of subbands, the number of channel layers, the product of at least two of the following parameters: the number of antenna ports, the number of codebook base vectors, or 2 times the number of codebook base vectors, the number of subbands, and the number of channel layers;

1≤e≤E, e is an integer.
The method according to claim 26, wherein the decomposition matrix H comprises E≥1 SVD decomposition, and the number of corresponding elements in the matrix of the e-th SVD decomposition is at least one of port number, subband number, and layer number Obtained by linear transformation.
The method according to claim 26, wherein the matrix H satisfies at least one of the following:

The number of rows is equal to the number of subbands, the number of columns is equal to the product of the number of ports and the number of layers, the mth row, n + (r-1) N column, or the mth row, r + (n-1) R column element The n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

The number of rows is equal to the number of antenna ports, and the number of columns is equal to the product of the number of subbands and the number of layers. The nth row, m + (r-1) M column, or the nth row, r + (m-1) R column The elements are the n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

The number of rows is equal to the number of layers, and the number of columns is equal to the product of the number of subbands and the number of antenna ports. The rth row, m + (n-1) M column, or the rth row, n + (m-1) N column The elements are the n-th port, the m-th subband, and the precoding coefficients on the r-th layer;

Among them, N is the number of antenna ports of the channel state information reference signal CSI-RS, M is the number of subbands included in the CSI feedback bandwidth, and R is the number of layers.
The method according to claim 26, wherein the decomposition matrix H comprises E≥1 SVD decomposition, receiving amplitude and phase information of elements in d left feature vectors U d corresponding to each decomposition, and receiving each decomposition corresponding to The amplitude and phase information of the elements in the d right eigenvectors V d .
The method according to claim 26, wherein the decomposition matrix H includes E≥1 SVD decomposition, and the precoding matrix assumed by the received subband CQI calculation is obtained according to a matrix product of transposed U d e and V d e , where , Where V d e is the first d column of the Kronecker product of the d left eigenvectors obtained by E-1 times of SVD decomposition other than e, and U d e is the d number of e-th SVD decompositions A matrix of left feature vectors.
The method according to claim 33, wherein the elements in the precoding matrix assumed in the subband CQI calculation are obtained according to corresponding elements after linear transformation of row or column numbering of the matrix product.
An information feedback terminal includes:

The decomposition module is configured to decompose the channel state information CSI matrix H to obtain the matrices U d and V d , where U d is a matrix of d columns, and multiple column vectors are orthogonal to each other; V d is a matrix of d columns. The column vectors are orthogonal to each other;

The feedback module is configured to feed back the amplitude and phase information of the elements in at least one of the d left eigenvectors U d and the amplitude and phase information of the elements in the d right eigenvectors V d .
An information feedback base station includes:

A receiving module configured to receive at least one of the following information fed back by the terminal UE: first amplitude and phase information of elements in d left feature vectors U d , and second amplitude and phase of elements in d right feature vectors V d Information, where U d is a d-column matrix, and the multiple column vectors are orthogonal to each other, V d is a d-column matrix, and the multi-column vectors are orthogonal to each other; M is a positive integer;

The determining module is configured to determine at least one of the first amplitude and phase information and the second amplitude and phase information as the channel state information CSI of the UE.
An electronic device includes a memory and a processor, and a computer program is stored in the memory, and the processor is configured to run the computer program to perform the method described in any one of claims 1 to 34.
A storage medium stores a computer program that is configured to execute the method described in any one of claims 1 to 34 when run.